CN116792167A

CN116792167A - Control method and device for small steam turbine

Info

Publication number: CN116792167A
Application number: CN202310877783.0A
Authority: CN
Inventors: 侯林鹏; 崔耀; 彭京启; 侯伟峰
Original assignee: Atos Shanghai Hydraulic Co ltd
Current assignee: Atos Shanghai Hydraulic Co ltd
Priority date: 2023-07-17
Filing date: 2023-07-17
Publication date: 2023-09-22

Abstract

The invention relates to the technical field of steam turbines, in particular to a control method and a device of a small steam turbine, wherein the control method of the small steam turbine comprises the steps of obtaining an operation instruction, wherein the operation instruction comprises target values of the rotating speed of a main rotating shaft, the steam pressure and the power generation of the steam turbine; acquiring first operation data and second operation data, wherein the first operation data comprises current detection values of the rotating speed of a main rotating shaft, steam pressure and power generation power of a steam turbine, and the second operation data comprises displacement of a diesel engine; and obtaining a valve position instruction according to the first operation data and the operation instruction, obtaining a control instruction according to the valve position instruction and the second operation data, and adjusting a gas valve of the steam turbine according to the control instruction. The invention realizes the full automation of the process in the operation of the turbine set, the real-time acquisition and operation of the operation data, and has the function of trend record, and the hydraulic oil engine has very high control precision and low cost, thereby meeting the market demand for controlling the small turbine set.

Description

Control method and device for small steam turbine

Technical Field

The invention relates to the technical field of steam turbines, in particular to a method and a device for controlling a small steam turbine.

Background

The small turbine in the prior art has small volume, low cost and power of usually less than 1MW. If the DEH system (digital electrohydraulic control system) of a large turbine is used for control, most of the functions of the control system are wasted greatly, and most of users cannot bear the control system at all due to poor economy. Therefore, the small turbine units in the present stage are mostly controlled by a mechanical governor in a conventional manner manually operated by a person during daily use.

However, the conventional approach to controlling a small turbine has the following disadvantages:

1) The mechanical speed regulator is not generally provided with a human-computer interface, and the state and data parameters of the turbine unit cannot be monitored during operation, so that the manual operation mode and the corresponding equipment configuration have low automation degree and basically depend on the experience of operators;

2) In general, the control function of the rotational speed circuit is only provided functionally, and therefore, the control accuracy is low and the reliability is poor.

3) The mechanical speed regulator has limited output force and slow action speed, and can affect the control precision, so that the requirement of the small turbine for quick control cannot be well met.

4) The lack of electronic protection means for blocking the steam inlet of the unit can not timely protect the safety of the unit under abnormal conditions.

The small turbine is also high-temperature, high-pressure and high-speed rotary steam power equipment, the precision and automation of the rotation speed control are very important, and along with the promotion of the modern industrial automation process, the requirements on the operation parameters of the small turbine on the control precision are also higher and higher. For example, when the rotational speed control accuracy is required to be within 0.2% of the rated value, the conventional manual control method cannot basically meet the requirement.

Disclosure of Invention

Based on the above, it is necessary to provide a control mode or a corresponding control device with a certain man-machine interaction, higher control precision and operation reliability, high response speed and electronic protection means to meet the industrial and market demands, aiming at the defects existing in the prior art.

In order to achieve the above object, the present invention provides a method and apparatus for controlling a small turbine, so as to solve the above technical problems.

In a first aspect, the present invention provides a method for controlling a small turbine, comprising:

acquiring a working instruction, wherein the working instruction comprises target values of the rotating speed of a main rotating shaft, the steam pressure and the power generation power of the steam turbine;

acquiring first operation data and second operation data, wherein the first operation data comprises current detection values of the rotating speed of a main rotating shaft, steam pressure and power generation power of a steam turbine, and the second operation data comprises displacement of an oil motor;

And obtaining a valve position instruction according to the first operation data and the operation instruction, obtaining a control instruction according to the valve position instruction and the second operation data, and adjusting a gas valve of the steam turbine according to the control instruction.

According to the current actual operation condition of the steam turbine, the control instruction for adjusting and controlling the steam turbine valve is generated by combining the target value (expected value) of the related parameters of the steam turbine input from the outside, and after the air valve is adjusted based on the control instruction, the related operation state (mainly the main rotating shaft rotating speed, the steam pressure, the power generation power and the like) in the subsequent operation condition of the steam turbine is gradually adjusted to the target value input from the outside, so that the closed-loop control of the steam turbine is realized.

Preferably, before the first operation data and the second operation data are acquired, the method includes:

the method comprises the steps of obtaining the current value of the EH oil pressure, comparing the current value of the EH oil pressure with a set threshold value, and judging whether a steam turbine can be started according to a comparison result:

when the comparison result shows that the current EH oil pressure is greater than or equal to a set threshold value, outputting a signal for allowing the unit to start;

and outputting a stop signal when the comparison result shows that the current EH oil pressure is smaller than the set threshold value.

The method comprises the steps of acquiring the state of a safety oil pressure switch of the steam turbine, analyzing and judging the state of the safety oil pressure switch, and outputting a start signal or a stop signal of the steam turbine.

Preferably, the acquiring the first operation data and the second operation data includes:

acquiring the current value of three paths of rotating speed data of a main rotating shaft of a steam turbine and the average value of the last detection period;

the current value of any path of rotating speed data is differenced from the average value, and when the difference value of the current value and the average value is smaller than a set threshold value, the current value of the path of rotating speed data is marked as a normal state, otherwise, the current value is marked as an error state;

judging the state mark of the current value of the three paths of rotating speed data:

when the three are in normal states, taking the numerical value of the three to be output by the middle person;

when any two are in a normal state, taking the large value of the two to output;

and outputting a shutdown signal when either one of the two is in an error state.

obtaining displacement of an actuating mechanism of the oil motor, wherein the displacement comprises at least two groups of detection data, and each group of detection data is generated by sampling an LVDT sensor;

and outputting a stop signal or outputting one group of detection data after analyzing and judging all the detection data of the displacement.

Preferably, after the obtaining the displacement of the actuator of the oil engine, the method further includes:

and demodulating each group of detection data of the displacement and outputting a demodulation result for subsequent analysis and judgment.

In a second aspect, the present invention provides a small turbine control apparatus comprising:

the man-machine interaction module is used for acquiring operation instructions, wherein the operation instructions comprise target values of the rotating speed of a main rotating shaft, the steam pressure and the power generation power of the steam turbine;

the first operation module is used for acquiring first operation data and second operation data, the first operation data comprise current detection values of the rotating speed of a main rotating shaft, the steam pressure and the power generation power of the steam turbine, and the second operation data comprise displacement of the oil motor;

the second operation module is set to obtain a valve position instruction according to the first operation data and the operation instruction, obtain a control instruction according to the valve position instruction and the second operation data, and adjust a gas valve of the steam turbine according to the control instruction.

Preferably, the small turbine control device includes:

The system comprises a first starting signal decision module, a second starting signal decision module and a third starting signal decision module, wherein the first starting signal decision module is used for acquiring the current value of the EH oil pressure, comparing the current value of the EH oil pressure with a set threshold value, and judging whether the steam turbine can be started according to a comparison result:

outputting a stop signal when the comparison result shows that the current EH oil pressure is smaller than the set threshold value;

the first starting signal decision module is connected with the first operation module.

Preferably, the small turbine control device includes:

the second starting signal decision module is used for acquiring the state of a security oil pressure switch of the steam turbine, analyzing and judging the state of the security oil pressure switch and then outputting a starting signal or a stopping signal of the steam turbine;

the second starting signal decision module is connected with the first operation module.

Preferably, the first operation module includes:

the displacement acquisition module is used for acquiring the displacement of an actuating mechanism of the oil motor, and the displacement comprises at least two groups of detection data, and each group of detection data is generated by sampling an LVDT sensor;

The displacement output module is used for outputting a stop signal or outputting one group of detection data after analyzing and judging all detection data of the displacement.

The beneficial effects are that: by adopting the technical scheme, the invention realizes the full automation of the process in the operation of the steam turbine unit, the real-time acquisition and operation of the operation data and the function of trend recording; because the hydraulic control is adopted in the hydraulic engine, the high-pressure (such as more than 14 Mpa) oil source provides very high output rigidity, so that the hydraulic engine has very high control precision and low cost, and the market demand for controlling the small turbine unit can be met.

Drawings

FIG. 1 is a flow chart of the steps performed in the method for controlling a small turbine in accordance with the present invention;

FIG. 2 is a first flowchart after adding a start condition determination based on the execution steps of FIG. 1;

FIG. 3 is a second flowchart after adding a start condition determination based on the execution steps of FIG. 1;

FIG. 4 is a flowchart illustrating steps performed to obtain a rotational speed of a main shaft of the steam turbine in FIG. 1;

FIG. 5 is a flowchart illustrating steps performed to obtain the displacement of the engine in FIG. 1;

FIG. 6 is a flow chart of adding sample signal demodulation based on the steps performed in FIG. 5;

FIG. 7 is a schematic view of a control apparatus for a small turbine in accordance with the present invention;

FIG. 8 is a schematic diagram of the connection of the frequency input channels of the present invention;

FIG. 9 is a schematic diagram of the connection of the digital signal input channels according to the present invention;

FIG. 10 is a schematic diagram of the connection of analog signal input channels according to the present invention;

FIG. 11 is a schematic diagram of the connection of analog signal output channels according to the present invention;

FIG. 12 is a schematic diagram of a connection structure of the displacement control module according to the present invention;

FIG. 13 is a schematic diagram of a connection structure of a digital signal output channel according to the present invention;

FIG. 14 is a schematic view of a functional connection of the structure of FIG. 7 at run time;

FIG. 15 is a schematic view of a steam turbine valve train controlled by the present invention.

Detailed Description

In order that the manner in which the invention is practiced, as well as the features and objects and functions thereof, will be readily understood and appreciated, the invention will be further described in connection with the accompanying drawings. It should be noted that the terms "first," "second," "third," "fourth," and the like in the description and in the claims, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments described herein may be implemented in other sequences than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product or apparatus that comprises a list of elements or units is not necessarily limited to those elements or units that are expressly listed or inherent to such product or apparatus, but may include other elements or units not expressly listed or inherent to such product or apparatus.

The present application provides a method for controlling a small turbine, which in some embodiments, as shown in fig. 1, includes steps S10 to S30, wherein,

step S10, acquiring an operation instruction, wherein the operation instruction comprises target values of the rotating speed of a main rotating shaft, the steam pressure and the power generation power of the steam turbine;

step S20, acquiring first operation data and second operation data, wherein the first operation data comprises current detection values of the rotating speed of a main rotating shaft, steam pressure and generation power of a steam turbine, and the second operation data comprises displacement of an oil motor;

and step S30, obtaining a valve position instruction according to the first operation data and the operation instruction, obtaining a control instruction according to the valve position instruction and the second operation data, and adjusting a gas valve of the steam turbine according to the control instruction.

Specifically, in step S10, an import operation command is externally input to obtain an expected value for adjusting the operation parameters of the steam turbine, and when the operation command is obtained, an external manual input or a timing/condition triggered content call may be used (here, a preset related operation command is imported into a control system corresponding to the present application by using computer software/program under a specific time or a specific condition, for example, a storage unit connected to the processing module/unit). In addition, the device can be connected to a network cluster of remote control through a field bus for remote regulation and centralized management.

In step S20, relevant state parameters of the current operation of the steam turbine are acquired, and these state parameters include state parameters related to the expected value in step S10, and also include state parameters closely related to the subsequent calculation (calculation of the control instruction in step S30). The first operation data and the second operation data are all various operation parameters related to the current operation state of the steam turbine, the operation parameters are acquired and fed back by sensors or transmitters arranged at various structural positions of the steam turbine, part of the data are used for comparing and calculating corresponding target values in operation instructions (for example, when the acquired sensor data are the rotating speed of a main rotating shaft of the steam turbine, the acquired sensor data are compared with the target values of the rotating speed of the main rotating shaft in the operation instructions) as feedback values after judgment, valve position instructions are output, and the other part of the data and the valve position instructions together generate control instructions for controlling the servo valves, so that closed-loop control logic for controlling the steam turbine is formed. The main rotating shaft rotating speed is fed back after detection and analysis through a speed measuring fluted disc matched with a rotating speed detection sensor, steam pressure and power generation power are directly fed back without judgment after being acquired through a site transmitter, and the steam pressure and the power generation power are used for calculating valve position instructions, and the output control result of a control instruction generated based on the valve position instructions directly influences the main rotating shaft rotating speed, the steam pressure and the power generation power, so that closed-loop control logic for adjusting relevant operation parameters is constructed. Taking the rotation speed as an example, the rotation speed corresponding data (actual value) is judged in the feedback process, one path of rotation speed data (three paths of rotation speed detection sensors are generally arranged at the speed measuring fluted disc of the main rotation shaft of the steam turbine) is taken after a certain judgment rule, and then is compared with the input rotation speed value (target value), and the control rotation speed is regulated according to the comparison result, so that a rotation speed closed loop control logic is constructed (here, the actual rotation speed and the target rotation speed both have influence on the generation of a valve position command, and the valve position command is directly connected with the generation of the control command). For another example, the steam pressure and the generated power are collected by the site transmitter and are directly fed back without judgment and then are used for calculating valve position instructions, and the output control result of the control instruction generated based on the valve position instructions directly influences the steam pressure, the generated power and the oil pressure of an EH system, so that closed-loop control logic for adjusting relevant operation parameters is constructed.

In step S30, a control command for controlling the gas valve of the steam turbine is finally generated based on the data acquired in step S20 and the data acquired in step S10, and the control command is issued to the actuator to adjust the gas valve of the steam turbine so as to achieve the operation state of the steam turbine corresponding to the expected value in the operation command.

Therefore, the invention is based on the current actual operation condition of the steam turbine and the target value (expected value) of the related parameters of the steam turbine input from the outside, and when in operation, the control command for adjusting and controlling the gas valve of the steam turbine is generated by utilizing the real-time feedback steam turbine state data and the input expected value, and then the gas valve is adjusted, so that the related operation state (mainly the main rotating shaft rotating speed, the steam pressure, the power generation power and the like) in the subsequent operation condition of the steam turbine is gradually adjusted to the externally input target value, thereby realizing the closed-loop control of the steam turbine.

In some embodiments, as shown in fig. 2, before the step S20, the method includes:

step S21, the current value of the EH oil pressure is obtained, the current value of the EH oil pressure is compared with a set threshold value, and whether the steam turbine can be started or not is judged according to the comparison result.

The determination of whether the steam turbine is bootable may be performed as follows:

when the comparison result shows that the current EH oil pressure is greater than or equal to a set threshold (for example, the difference value of the current EH oil pressure and the set threshold is greater than or equal to 0), outputting a signal for allowing the unit to start;

when the comparison result shows that the current EH oil pressure is smaller than the set threshold (for example, the difference between the current EH oil pressure and the set threshold is smaller than 0), a stop signal is output.

Specifically, an EH oil pressure reference value may be preset as a set threshold value to determine whether the current EH oil pressure meets the start requirement of the turbine (for example, the threshold value is set in the stage of importing the operation command, or the threshold value is built in a storage unit connected with the device of the present application for the operation module to call as required), and then the actual EH oil pressure value is obtained through an oil pressure transmitter of the turbine and compared with the set threshold value to determine whether the actual EH oil pressure meets the condition. For example, setting 5Mpa as a threshold, when the detected EH oil pressure actual measurement value is greater than 5Mpa, the steam turbine is considered to have a start condition, that is, the current condition of the EH oil system is enough to support the steam turbine to work, otherwise, the EH oil system is considered to have a problem, and start is prohibited.

The EH oil pressure is the operating pressure of the EH oil pump, which supplies high-pressure fire-resistant oil to the steam turbine and drives each actuator of the steam turbine. The EH oil pump can normally operate only when the EH oil pressure reaches a specific value, so that the EH oil pump provides power oil to the main valve and the regulating valve of the steam turbine, and the steam turbine can meet the starting condition. The detection value of the EH oil pressure is fed back upwards after being acquired by a transmitter on site. As shown in fig. 7 and 10, the present application obtains EH oil pressure and other data sampled in analog by establishing a set of analog signal input channels 32, and a channel AI3 in the set of analog signal input channels 32 is connected to an EH oil pressure transmitter 2005, and the obtained actual measurement data is fed back to an upper level computing unit (i.e., a first computing module described later). Referring to fig. 14, when the measured data reaches the set threshold, a signal 901 for allowing the steam turbine to start is output to the second operation module 22 by the first operation module 21, the second operation module 22 performs subsequent data operation and processing after receiving the signal 901, and when the measured data does not reach the set threshold, the second operation module 22 does not perform subsequent processing.

In some embodiments, as shown in fig. 3, before the step S20, the method includes:

step S22, acquiring the state of a safety oil pressure switch of the steam turbine, analyzing and judging the state of the safety oil pressure switch, and outputting a start signal or a stop signal of the steam turbine.

It should be noted that, the judgment of whether to start the steam turbine needs to be determined by combining the states of the safety oil pressure switches, the safety oil pressure switches generally comprise three switches, and after the judgment of the states of the switches is analyzed and judged by adopting preset rules, a signal for allowing the steam turbine to start or a stop signal is selectively output according to the judgment result.

In some of the embodiments, referring to fig. 7 and 9, the present invention provides a set of digital signal input channels 33 to obtain the state of the security oil pressure switch, and outputs the result or a stop signal to the upper processing unit after making an analysis judgment. Fig. 9 shows a structure in which the digital signal input channel 33 includes channels DI1 to DI4, where the channels DI1 to DI3 are respectively connected to three security oil pressure switches 1006, and after obtaining the states of the switches, the digital signal input channel outputs the result according to the rule of "two-out-of-three" after judging:

when any two of the three safety oil pressure switches 1006 are turned on, a signal for allowing the steam turbine to start is output. For example, as in the structure shown in fig. 9, when:

1) Both the channel D1 and the channel D2 are conducted;

2) Channel D2 and channel D3 are both conductive;

3) Both channel D3 and channel D1 are conductive.

In either case, a signal for allowing the steam turbine to start may be output to the upper stage.

In the above example, the signal receiving points corresponding to the channels D1 to D3 may be considered as normally open points, in which case "on" of each channel may be considered as that the channel receives the output signal of the safety hydraulic switch, and if the channel does not receive the switching value signal, the channel is considered as not being on.

Referring to fig. 14, the first operation module 21 transmits a signal 902 for allowing the steam turbine to start to the second operation module 22, and the second operation module 22 continues the subsequent operation process upon receiving the signal 902.

In some embodiments, as shown in fig. 4, the step S20 includes:

step S2011, obtaining the current value of three paths of rotating speed data of a main rotating shaft of the steam turbine and the average value of the last detection period;

step 2012, the current value of any path of rotation speed data is differenced from the average value, and when the difference value of the current value and the average value is smaller than a set threshold value, the current value of the path of rotation speed data is marked as a normal state, otherwise, the current value is marked as an error state;

Step S2013, judging the status flag of the current value of the three paths of rotational speed data:

It should be noted that, when three paths of rotational speed data of the main rotating shaft of the steam turbine are detected, the average value of each detection period is calculated and then stored in a storage unit, and when the next detection period is performed, the average value is called to be used as a judging basis for judging whether the rotational speed data in the current detection period is normal or not. The judgment of the current rotation speed detection value of the rotation speed data and the rotation speed average value of the upper period comprises two stages of judgment, wherein the first stage of judgment is used for judging the correctness or the mistake of the rotation speed detection value, and the second stage of judgment is used for selecting the finally output rotation speed detection value or judging whether to output a stop signal or not based on the result of the first stage of judgment.

As shown in fig. 7, the present invention sets a set of frequency input channels 31 to acquire rotational speed data and output a final result to an upper stage or output a stop signal after performing an analysis and judgment. As shown in fig. 8, the frequency input channel 31 includes channels PI1 to PI3, each of which is connected to a tachometer probe 20011 disposed on a tachometer fluted disc side, and referring to fig. 15, the tachometer fluted disc 2001 is disposed on a main shaft 1001 of the steam turbine. A set threshold is preset as a basis for comparison and judgment, and the threshold can be regarded as the error tolerance of the speed measurement. When the first-stage judgment is carried out, comparing the average value with the current value of any rotation speed detection value, when the difference between the average value and the current value of any rotation speed detection value reaches a certain rotation speed (namely, setting a threshold value, such as setting 50 to the threshold value, if the difference is greater than or equal to 50 rotations, considering that the rotation speed detection value is wrong, otherwise, the rotation speed detection value is correct, and if the difference is not less than 50 rotations, considering that the current value of the rotation speed detection value is wrong (marked/assigned as N), otherwise, considering that the rotation speed detection value is correct (marked/assigned as Y), and carrying out state marking on each path of rotation speed detection value according to the judgment result;

And when the second-stage judgment is carried out, outputting a stop signal when the current value of the rotation speed detection values of any two paths is wrong according to the result of the first-stage judgment, taking the rotation speed detection value of the intermediate value as final output rotation speed data when the three paths are normal, and taking the rotation speed detection value with larger value as final output rotation speed data when any two paths are normal.

The output rotating speed data are contained in the first operation data and serve as the basis of subsequent data processing, so that closed-loop control of rotating speed adjustment is realized after the rotating speed of the main rotating shaft of the steam turbine is subjected to subsequent adjustment.

In the configuration shown in fig. 8, the determination flow is executed in the first arithmetic block 21.

In some embodiments, as shown in fig. 5, the step S20 includes:

step S2021, obtaining displacement of an actuating mechanism of the oil motor, wherein the displacement comprises at least two groups of detection data, and each group of detection data is generated by sampling an LVDT sensor;

and step S2022, after analyzing and judging all the detection data of the displacement, outputting a stop signal or outputting one group of detection data.

It should be noted that, the pneumatic motor matched with the steam turbine is used for adjusting the air valve of the steam turbine, and the pneumatic motor is provided with a group of two LVDT sensors on the action executing mechanism (such as a piston or a piston rod) for detecting and checking the displacement corresponding to the action stroke.

As shown in fig. 15, in the steam turbine air valve adjusting mechanism, an LVDT sensor 2003 is provided at the engine 1003, and as shown in fig. 14, a feedback signal of the LVDT sensor 2003 is demodulated by a demodulation circuit and then transmitted to a superior processing unit to be operated and processed to generate a corresponding control command, and the servo valve is adjusted by the control command, so that the air valve of the steam turbine is driven to act after the engine is controlled to act, and the position of the steam turbine is closed-loop controlled (the position here refers to a displacement amount corresponding to an action stroke change of an engine executing mechanism fed back by the LVDT sensor). In the present invention, after acquiring the data of two LVDT sensors 2003, the two sets of data are subjected to judgment and analysis, and then a stop signal is output or one of the two sets of data is output. Referring to fig. 12, two sets of data are defined as LVDT1 and LVDT2, and the analytical determination of both can be performed as follows:

1) LVDT1 is less than or equal to 0, and LVDT2 is taken for output;

2) LVDT2 is less than or equal to 0, and LVDT1 is taken for output;

3) LVDT1 is less than or equal to 0, LVDT2 is less than or equal to 0, and a shutdown signal is output;

4) LVDT1>0 and LVDT2>0, the larger of the two being taken for output.

The output displacement data are contained in the first operation data and are used as the data basis for subsequent judgment and used for subsequent adjustment of the oil motor so as to realize the position closed-loop control of the steam turbine.

In some embodiments, as shown in fig. 6, after the step S2021, the method further includes:

step S20211 demodulates each set of detection data of the displacement amount, and outputs a demodulation result for subsequent analysis and judgment.

It should be noted that, the output signal of a common LVDT sensor is generally an analog signal, so in these cases, it is necessary to perform conversion to generate a corresponding digital signal before performing numerical analysis and judgment.

This step is performed before step S2022.

The present invention further provides a small turbine control device, in some embodiments, as shown in fig. 7 and 14, the small turbine control device includes a man-machine interaction module 1, a first operation module 21 and a second operation module 22, where the man-machine interaction module 1 is configured to obtain an operation instruction, and the operation instruction includes a main shaft rotation speed, a steam pressure, and a target value of power generation of the turbine;

the first operation module 21 is configured to acquire first operation data and second operation data, wherein the first operation data includes current detection values of a main rotating shaft rotating speed, steam pressure and power generation of the steam turbine, and the second operation data includes displacement of the oil motor;

The second operation module 22 is configured to obtain a valve position command based on the first operation data and the operation command, obtain a control command based on the valve position command and the second operation data, and adjust a gas valve of the steam turbine based on the control command.

In the above embodiment, the output end of the man-machine interaction module 1 and the output end of the first operation module are both connected to the input end of the second operation module 22, and respectively transmit an externally input operation instruction and turbine operation data (part of data is directly transmitted, and the other part of data is transmitted to part of data after analysis processing) to the second operation module 22 for logic operation, and then output a control instruction of a servo valve for adjusting the air valve;

the input end of the first operation module 21 is connected with each sensor and a transmitter of the steam turbine to acquire the operation data of the steam turbine;

referring to fig. 14 and 15, other output ends of the first operation module 21 are connected with protection devices such as a shutdown solenoid valve 3001, an OPC solenoid valve 3002, an ETS protection switch and the like of the steam turbine, so that a shutdown response can be made according to analysis and judgment for acquiring real-time operation data of the steam turbine under the condition that the second operation module 22 is not involved.

In addition, the man-machine interaction module 1 includes an input device 101 and an output device 102, a job instruction is sent to the second operation module 22 through the input device 101, relevant information is output through the input device 102, and the output device 102 includes a display, a printer, and an audible and visual alarm.

In the present invention, the man-machine interaction module 1 may be connected to the second operation module 22 through an ethernet communication port. The first operation module 21 and the second operation module 22 are mutually connected and relatively independent, and different data processing is completed between the first operation module and the second operation module, so that the processing efficiency of related data can be effectively improved, and the control efficiency and the instantaneity of the control method are improved.

Referring to FIG. 7, the present invention in some embodiments provides a frequency input channel 31, an analog signal input channel 32, a digital signal input channel 33, and a displacement acquisition channel 401 (implemented by displacement control module 40) to acquire transmitter and sensor data, communicate with external systems;

in some embodiments, as shown in fig. 7 and 8, the frequency input channel 31 includes channels PI1 to PI3, each of which is connected to a tachometer probe 20011 disposed on a tachometer fluted disc side, and referring to fig. 15, the tachometer fluted disc 2001 is disposed on a main shaft 1001 of the steam turbine.

In some of these embodiments, as shown in fig. 7 and 10, the analog signal input channel 32 includes channels AI 1-AI 4, channel AI1 is connected to the power transmitter 2002, channel AI2 is connected to the main vapor pressure transmitter 2004, channel AI3 is connected to the EH pressure transmitter 2005, and channel AI4 is used as a backup channel, and may be connected to the DCS control system 2006 to obtain related control commands.

In some of these embodiments, as shown in fig. 7 and 9, the digital signal input channel 33 includes channels DI 1-DI 4, channels DI 1-DI 3 are connected to three safety oil pressure switches 1006, and channel DI4 is connected to an ETS protection system 2007 (turbine trip protection system). In some preferred embodiments, a photoelectric isolator 1007 is disposed between each of the channels D1-D4 and the first computing module 21.

In some of these embodiments, as shown in fig. 7 and 12, the displacement acquisition channel 401 is connected to the LVDT sensor 2003 and includes a demodulation circuit MODEM to convert the sampled sensor data into a data-processable electrical signal form.

Referring to fig. 7, the present invention provides an analog signal output channel 51, a digital signal output channel 52, and a valve position control channel 402 (implemented by the displacement control module 40) to output control instructions, drive solenoid valves, and communicate with an external system.

In some embodiments, as shown in fig. 7 and 11, the analog signal output channel 51 includes a channel AO1 and a channel AO2, where the channel AO1 outputs a smaller current and controls the corresponding valve actuator to operate, and the channel AO2 outputs a larger current and controls the corresponding valve actuator to operate.

In some of these embodiments, as shown in FIGS. 7 and 13, the digital signal output channel 52 includes channels DO 1-DO 4, channel DO1 connects to the shutdown solenoid valve 3001, channel DO2 connects to the OPC solenoid valve 3002, channel DO3 connects to the ETS protection system 2007, and channel DO4 connects to the DCS control system 2006. In some preferred embodiments, as shown in fig. 13, a solid state relay 1008 is disposed between any digital signal output channel and the first computing module 21.

In some of these embodiments, as shown in FIGS. 7 and 12, the valve position control passage 402 connects with a servo valve 1005.

The method judges the starting condition of the steam turbine by arranging the first starting signal decision module and the second starting signal decision module.

In some embodiments, the small turbine control apparatus includes a first start signal decision module configured to obtain a current value of EH oil pressure, compare the current value of EH oil pressure with a set threshold, and determine whether the turbine is started based on a comparison result: when the comparison result shows that the current EH oil pressure is greater than or equal to a set threshold value, outputting a signal for allowing the unit to start; outputting a stop signal when the comparison result shows that the current EH oil pressure is smaller than the set threshold value;

the first start signal decision module is connected to the first operation module 21.

Specifically, as shown in fig. 7 and 10, the feedback data of each transducer of the steam turbine is acquired through an analog signal input channel 32, and the feedback data comprises the power generated by the steam turbine, the steam pressure and the EH oil pressure. Analog signal input path 32 includes paths AI 1-AI 4, path AI1 being connected to power transmitter 2002 for deriving turbine power generation, path AI2 being connected to main steam pressure transmitter 2004 for deriving steam pressure, and path AI3 being connected to EH pressure transmitter 2005 for deriving EH oil pressure. The first start signal decision module is constructed by the channels AI3 and EH pressure transmitter 2005 to realize the function;

The channel AI4 may connect to the DCS control system 2006 to obtain the associated control commands.

As shown in fig. 14, the first start signal 901 generated by the first start signal decision module allows the steam turbine to start, and the first start signal 901 is sent by the first operation module 21 to the second operation module 22 to decide whether the operation instruction further performs the subsequent operation.

In some embodiments, the small turbine control device includes a second start signal decision module configured to obtain a state of a safety oil pressure switch of the turbine, analyze and judge the state of the safety oil pressure switch, and output a start signal or a stop signal of the turbine;

the second start signal decision module is connected to the first operation module 21.

Specifically, as shown in fig. 7 and 9, the present invention sets the digital signal input channel 33 to obtain the state of the safety oil pressure switch, including channels DI1 to DI4, wherein, channels DI1 to DI3 are connected to three safety oil pressure switches 1006, and channel DI4 is connected to an ETS protection system 2007 (turbine tripping protection system).

In some embodiments, the first operation module includes a displacement amount acquisition module and a displacement amount output module, where the displacement amount acquisition module is configured to acquire a displacement amount of an actuator of the servomotor, where the displacement amount includes at least two sets of detection data, and each set of detection data is generated by sampling by an LVDT sensor;

Specifically, as shown in fig. 7 and 12, the present invention sets a displacement control module 40, which includes two paths of displacement acquisition channels 401 (corresponding to each LVDT sensor 2003, only one path is shown in fig. 12 for demonstration) and one valve position control channel 402 (which sends a control command to the servo valve 1005), and the displacement control module 40 is further connected to a stop solenoid valve 3001 to output a stop signal in case the acquired LVDT data does not meet the requirement. The displacement acquisition channel 401 realizes the function of a displacement acquisition module, and the valve position control channel 402 realizes the function of a displacement output module. As shown in fig. 12 and 15, the LVDT sensor 2003 is provided at an actuator of the motor 1003, and its output end is connected to a MODEM circuit MODEM, and the demodulated displacement is analyzed to determine whether the LVDT sensor has a failure or a disconnection, and when all the LVDT sensor has a failure or a disconnection, a stop signal is output to the stop solenoid valve 3001, and when one of the LVDT sensor has a failure or a disconnection, data of the other sensor is output, and when both of the LVDT sensor and the LVDT operate normally, larger data is output.

The invention can directly collect LVDT displacement signals under the condition of having two paths of LVDT collecting channels, and carry out modulation and demodulation operation internally without singly arranging an LVDT transducer, thereby reducing the manufacturing cost. Meanwhile, the first operation module processes valve position data corresponding to the valve position instruction and LVDT actual measurement data and then outputs a control instruction to a servo valve port, so that a hydraulic servo control function of a closed loop of the oil motor is realized, an external servo card is not needed, and the manufacturing cost is greatly reduced.

In some embodiments, as shown in fig. 7 and 11, the present invention includes an analog signal output channel 51. The analog signal output channel 51 includes two channels, namely a channel AO1 and a channel AO2, wherein the channel AO1 can output a smaller current and then control the corresponding valve actuator to work, and the channel AO2 can output a larger current and then control the corresponding valve actuator to work.

In the field device environment of the steam turbine, various valves are generally classified into a standard type and a high-power type according to the magnitude of the driving current (usually, 20mA is used as a boundary) of the action actuator. The standard valve needs 4mA to 20mA current drive, and the high-power valve needs 20mA to 160mA high current drive, so after the analog signal output channel 51 is set in the invention, two types of driving currents can be correspondingly output to drive the actuating mechanism of the standard valve and the high-power valve, such as some valve actuators with non-LVDT electric displacement feedback (the valve actuator is provided with a closed-loop device, and the AO channel only needs to output signals), for example: voith valve, TG actuator. Fig. 11 shows a structure in which a channel AO1 is defined as a standard current device driving channel for driving a standard valve 2008, the output driving current thereof is 4 mA-20 mA, a channel AO2 is defined as a high current device driving channel for driving a high power valve 2009, and the output driving current thereof is in a range of 20 mA-160 mA.

In some embodiments, as shown in fig. 7 and 13, the present application includes a digital signal output channel 52. The digital signal output channel 52 comprises a channel DO 1-a channel DO4, wherein the channel DO1 is defined as a shutdown signal output channel, and the shutdown signal output channel is connected with a shutdown electromagnetic valve 3001 and then drives the shutdown electromagnetic valve 3001 to work so as to stop the steam turbine; the channel DO2 is defined as an overspeed protection signal output channel which is connected with the OPC electromagnetic valve 3002 to drive the OPC electromagnetic valve to work; the channel DO3 is defined as an ETS signal output channel, and sends a shutdown signal to the ETS protection system after the ETS signal output channel is connected with the ETS protection system to realize emergency protection. Channel DO4 may connect to DCS control system 2006 (along with channel AI4 to enable communication with the DCS system).

In some embodiments, as shown in fig. 13, a solid state relay 1008 is disposed between any digital signal output channel and the first operation module 21.

In the present application, a stop signal is output to the stop solenoid valve 3001 or the OPC solenoid valve 3002 to cause the stop signal to act, thereby generating a stop effect. The stop signals in the application comprise stop signals (shown in fig. 8) generated in the process of judging the rotating speed data, stop signals (shown in fig. 9) generated by the state feedback result of the tripping protection system (ETS), stop signals (shown in fig. 9) generated in the process of judging the state of the safety oil pressure switch and stop signals (shown in fig. 12) generated in the process of judging the displacement detection data of the actuating mechanism of the oil motor. For example, fig. 15 shows a configuration in which a stop solenoid valve 3001 and an OPC solenoid valve 3002 are provided in a control link between a servo valve 1005 and an engine 1003, and either one of them is not operated, so that the control link between the servo valve 1005 and the engine 1003 is disconnected. Therefore, when the rotating speed detection link outputs a shutdown signal, the security oil pressure switch outputs the shutdown signal in the state analysis and judgment process, and the LVDT data outputs the shutdown signal in the analysis and judgment process, shutdown is caused. In addition, when the main shaft of the steam turbine is overspeed to a rated speed by a certain proportion, a driving signal for generating the OPC electromagnetic valve 3002 is triggered, so that the control connection between the servo valve 1005 and the engine 1003 is disconnected after the OPC electromagnetic valve 3002 is driven. Because the modes of real-time detection of the rotation speed of the main rotation shaft, comparison of the detection value with the set rotation speed and the like are all the prior art, the application is not further described.

Fig. 15 shows a control structure of a steam turbine constructed based on the control device of the present invention, in which a tachometer disc 2001 is disposed on a main shaft 1001 of the steam turbine, a generator 1002 and a power transmitter 2002 are disposed between the main shaft 1001 and a power grid B, high temperature steam a enters a regulating steam valve 1004, a motor 1003 performs opening control on the regulating steam valve 1004, and an LVDT sensor 2003 is disposed at an actuator of the motor 1003. As is clear from fig. 14, when the two signals are not received, the servo valve 1005 for controlling the hydraulic motor 1003 is restricted by the signal 901 and the signal 902, and the servo valve 1005 cannot be controlled. A stop solenoid valve 3001 (driven by the channel DO 1) and an OPC solenoid valve 3002 (driven by the channel DO 2) are provided between the servo valve 1005 and the prime mover 1003.

Fig. 14 shows a control manner of operating the control structure of fig. 15, where a working command 905 (including the main shaft rotation speed, the steam pressure, and the expected/target value of the generated power) is issued by the man-machine interaction module 1 to the second operation module 22, the first operation module 21 feeds back the feedback data 904 (including the main shaft rotation speed, the steam pressure, and the measured/determined value of the generated power) of the sensor and the transmitter to the second operation module 22, and at the same time, the first operation module 21 also feeds back the signal 901 and the signal 902, and when the signal 901 and/or the signal 902 are not received, the second operation module 22 does not perform the next processing on the input or feedback;

The second operation module 22 compares the input and fed-back data and performs PID operation processing to generate a valve position command C, where the valve position command C includes other valve control signals 903 output through the channel AO1 and the channel AO2 for controlling other valves;

the first operation module 21 analyzes the LVDT sensor feedback data processed by the demodulation circuit MODEM, outputs final displacement measured data, compares the final displacement measured data with the valve position command C, performs PID operation processing, generates a control command SV, and sends the control command SV to the servo valve 1005, and after the servo valve 1005 is controlled by the control command SV to operate, the closed-loop control of the throttle valve 1004 is realized.

The application field of the application is a small turbine unit with the size smaller than 1MW, the data acquisition and execution structure control are processed relatively independently through a double operation assembly (a first operation module 21 and a second operation module 22) (the application is characterized in that the second operation module 22 is used for completing the external man-machine interaction and the calculation of all configuration logics, the first operation module 21 is used for completing the signal sampling and analysis judgment of all input channels and the output of the processing result of the second operation module 22), and the turbine adjusting steam valve 1004 is directly driven by acquiring related signals such as the turbine rotating speed, the steam pressure, the power generation and the like and outputting control instructions to a hydraulic servo actuator (a servo valve 1005) based on the signals so as to realize the effect of accurately adjusting the turbine rotating speed, the steam pressure and the power generation under the condition of blocking the turbine inlet steam. The two relatively independent operation components respectively bear corresponding calculation load and work task, thereby reducing the generation of high energy consumption and high heating problems of devices caused by unified calculation by adopting a single operation component, and avoiding the phenomena of unstable system, downtime and the like caused by overload work.

In summary, the application adopts a double control chip mode to carry out apportionment processing for specific tasks. A single CPU (for example, an operation module is used for processing the total workload of the first operation module and the second operation module) is required to process both logic operation and all data transmission, which will lead to a larger processing load of the CPU, higher energy consumption, correspondingly higher heat dissipation load, higher system instability, and equipment paralysis caused by continuous working for a period of time or downtime; the mode of double CPU solves this problem well, and makes the system more stable and reliable.

It should be noted that, when the structure of the application is implemented, the structure can be realized by independently developing the product mode of the special controller, thereby effectively reducing the cost and the use requirement and maximally carrying out targeted design and research and development according to the actual requirement.

The foregoing has shown and described the basic principles and main features of the present application and the advantages of the present application. It will be understood by those skilled in the art that the present application is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present application, and various changes and modifications may be made without departing from the spirit and scope of the application, which is defined in the appended claims. The scope of the application is defined by the appended claims and equivalents thereof.

Claims

1. A method of controlling a small turbine, the method comprising:

2. The method of claim 1, wherein prior to the acquiring the first operation data and the second operation data, comprising:

3. The method of claim 1, wherein prior to the acquiring the first operation data and the second operation data, comprising:

4. The method of claim 1, wherein the acquiring the first and second operation data comprises:

5. The method of controlling a small turbine according to any one of claims 1 to 4, wherein the acquiring the first operation data and the second operation data includes:

6. The method according to claim 5, wherein the step of obtaining the displacement amount of the actuator of the engine further comprises:

7. A small turbine control apparatus, comprising:

8. The small turbine control apparatus as claimed in claim 7, wherein the small turbine control apparatus comprises:

9. The small turbine control apparatus as claimed in claim 7, wherein the small turbine control apparatus comprises:

10. The small turbine control apparatus of claim 7, wherein the first operation module comprises: